This invention relates to a process, and an apparatus, for producing interior vehicular trim, which process is feasible for readily mass-producing interior vehicular trim of good appearance, comprising a substrate whose surface has been decoratively covered with a nap-raised ornamental member such as moquet and carpets and with a synthetic resin surface material.
Widely known and disclosed in Japanese Patent Publication No. 24008/1984 is a process for producing interior automotive trim, comprising covering the entire surface of a substrate to which a nap-raised ornamental member is partly applied, with a synthetic resin surface material, welding the surface material on the peripheral edge of said ornamental member, and removing said synthetic resin surface material at its part covering the ornamental member and along the weld line.
However, many of the synthetic resin surface materials to be used in this type of process are combined with a foamed layer to give a thickness of 2 mm or more.
Accordingly, in an attempt to effect welding and melt-cutting of such a surface material simultaneously, welding pressure may be insufficient if the projection of the melt-cutter from a weld plate for high frequency welding is small, resulting in the failure of giving a clear weld pattern. Alternatively, if an increased welding pressure is used for obtaining clear weld pattern, it will cause sparking. Thus, welding must have been done without increasing the welding pressure and then the setting of the projection of the melt-cutter from the weld plate is great to make thinner the welded portion to facilitate manual stripping off of the surface material along said portion. Such procedures have been troublesome.
There has been also a problem as follows: When the surface of the substrate to which the nap-raised ornamental member has been partly applied is covered with the synthetic resin surface material and part of the surface material is welded on the peripheral edge of said ornamental member, the welded synthetic resin surface material may become protuberant as a superfluously thick portion along the weld line to melt the nap of the ornamental member or to cause the nap-lying to bring about what is called a whitening phenomenon wherein ornamental member looks whitish along the weld line, resulting in an unsatisfactory product appearance.